Final answer:
NSAIDs cause gastric side-effects through the inhibition of cyclooxygenase (COX) enzyme, which leads to a decrease in protective prostaglandins in the stomach, causing increased susceptibility to damage by gastric acid and potential gastrointestinal damage over long-term use.
Step-by-step explanation:
Nonsteroidal anti-inflammatory drugs (NSAIDs) cause gastric side-effects primarily through their action on prostaglandin synthesis. These drugs, including aspirin, ibuprofen, and naproxen, inhibit the enzyme cyclooxygenase (COX), which is necessary for the conversion of arachidonic acid to prostaglandins. While prostaglandins are associated with inflammation and pain, they also play a crucial role in protecting the stomach lining by stimulating the production of gastric mucus and bicarbonate. The inhibition of COX reduces the protective prostaglandins, making the gastric mucosa more susceptible to damage by gastric acid, resulting in ulcers and gastrointestinal bleeding.
Long-term use of NSAIDs can lead to significant gastrointestinal damage, including ulcers and bleeding. This occurs because the protective effects of prostaglandins within the gastrointestinal tract are compromised. Additionally, prostaglandins help maintain normal kidney function, blood flow, and the process of blood clotting, and the impairment of their synthesis may result in kidney damage and increased risk of heart attack.